Process for manufacturing scrubby substrates and substrates made therefrom

Abstract

In-line processes for producing scrubby substrates, and related scrubby substrate cleaning articles. The process may include melting a polymer resin material, and extruding or otherwise dispensing the molten polymer resin material through one or more orifices of a heated nozzle, into a stream of hot inert gas, which attenuates the molten resin, so that the resin forms into elongated globules (rather than fibers or filaments). Such globules may have irregular cross-section and/or irregular thickness along a length of the globules. Alternatively, the molten resin may be formed into substantially continuous or discontinuous string or chain pattern of abrasive fibers, exhibiting a high frequency, low amplitude substantially linear pattern on the base substrate. In either case the globules or abrasive fibers are collected onto at least a portion of a base substrate layer to form a scrubby substrate that is more abrasive than typical meltblown materials.

The invention claimed is: 
     
       1. An in-line process for producing a scrubby substrate, the process comprising:
 (a) melting a polymer resin material; 
 (b) extruding or otherwise dispensing the molten polymer resin through one or more orifices of a heated nozzle into a stream of hot inert gas which attenuates said molten resin into elongated globules that form a stream of such globules without forming fibers or filaments; 
 (c) creating elongated globules having an irregular cross-section and/or an irregular thickness along a length of said elongated globules; 
 (d) collecting said globules onto at least a portion of a surface of a base substrate layer so that the globules bond directly to the base substrate layer as the molten polymer resin cools, said globules being abrasive once cooled; 
 wherein a spacing between the one or more orifices of the nozzle and the base substrate layer is less than 6 inches, to aid in globule adhesion to the base substrate layer. 
 
     
     
       2. The process of  claim 1 , wherein said polymer resin is selected from the group consisting of polypropylene, polyethylene, polyesters, high-density polypropylene, low-density polypropylene, polystyrene, polyamides, nylon, polyvinylidenes, polyurethane, polyurea, polyethylene terephthalate, polylactic acid, viscose, rayon, epoxy resin, silicone resins, and copolymers and combinations thereof. 
     
     
       3. The process of  claim 1 , wherein the molten resin has a meltflow rate of 35 to 400 grams/10 minutes. 
     
     
       4. The process of  claim 1 , further comprising adding an abrasive particulate material to the molten polymer resin material. 
     
     
       5. The process of  claim 1 , wherein the abrasive globules are deposited in a stripe pattern that covers only a portion of one face of the base substrate layer. 
     
     
       6. The process of  claim 1 , wherein the abrasive globules are discontinuous, having irregular lengths. 
     
     
       7. A scrubby substrate formed according to the process of  claim 1 . 
     
     
       8. A scrubby substrate as recited in  claim 7 , wherein the abrasive globules cover only a portion of one face of the base substrate layer. 
     
     
       9. An in-line process for producing a multi-layer scrubby substrate, the process comprising:
 (a) melting a polymer resin material; 
 (b) extruding or otherwise dispensing the molten polymer resin through a plurality of orifices of a heated nozzle into a stream of hot inert gas which attenuates said molten resin into fibers and creates a stream of abrasive fibers; and 
 (c) depositing said abrasive fibers onto at least a portion of a face of a base substrate layer in a substantially linear high frequency low amplitude pattern so that the molten polymer resin adheres directly to the base substrate layer as it cools to create an abrasive scrubby layer on the face of the base substrate layer; 
 wherein the polarity of the polymer resin matches the polarity of the face of the base substrate layer so that good adhesion is achieved between the abrasive fibers and the base substrate layer. 
 
     
     
       10. The process of  claim 9 , wherein said polymer resin is selected from the group consisting of polypropylene, polyethylene, polyesters, high-density polypropylene, low-density polypropylene, polystyrene, polyamides, nylon, polyvinylidenes, polyurethane, polyurea, polyethylene terephthalate, polylactic acid, viscose, rayon, epoxy resin, silicone resins, and copolymers and combinations thereof. 
     
     
       11. The process of  claim 9 , wherein the scrubby layer comprises an abrasive particulate material. 
     
     
       12. The process of  claim 11 , wherein the abrasive particulate material is added to the scrubby layer during a process selected from the group consisting of: substrate winding, creating interleaved substrate stacks, attaching multiple layers of substrate articles together, adding abrasive particulate material to the molten polymer resin as it is dispensed from the orifices, and any combinations thereof. 
     
     
       13. The process of  claim 9 , wherein the molten resin has a meltflow rate of 35 to 400 grams/10 minutes. 
     
     
       14. The process of  claim 9 , wherein the abrasive fibers adhere to one another, creating a substantially continuous string or chain of fibers wherein the string or chain has an irregular cross-section along its length. 
     
     
       15. The process of  claim 9 , wherein the abrasive fibers form discontinuous strings or chain of fibers. 
     
     
       16. The process of  claim 9 , further comprising the step of loading a cleaning composition onto one or more layers of said scrubby substrate. 
     
     
       17. A scrubby substrate formed according to the process of  claim 9 . 
     
     
       18. A scrubby substrate as recited in  claim 17  wherein the abrasive fibers cover only a portion of one face of the base substrate layer.